Association of dietary fiber intake with all-cause and cardiovascular mortality in postmenopausal U.S. women: A NHANES 1999-2018 cohort study.
Level 3 - non-randomized controlled study
Prospective cohort study linking NHANES survey data to mortality records
PubMed 41161230 · doi:10.1016/j.maturitas.2025.108752
What was done
Researchers analyzed 7,708 postmenopausal U.S. women from the 1999–2018 National Health and Nutrition Examination Survey (NHANES) linked to mortality data over a median follow-up of 121 months. Dietary fiber intake (g/day) was assessed using 24-hour dietary recalls. Multivariable Cox proportional hazards models calculated hazard ratios (HRs) for all-cause and cardiovascular disease (CVD) mortality, adjusting for age, sex, ethnicity, education, poverty-income ratio, smoking, alcohol use, physical activity, and body mass index.
What was found
Mean baseline dietary fiber intake was 14.75 ± 7.5 g/day. During follow-up, 2,116 deaths occurred (27.5%), including 657 CVD deaths (8.5%). Fiber intake was inversely associated with mortality risk. For participants consuming <7.9 g/day, each 5 g/day increase was associated with a 7% reduction in all-cause mortality (HR = 0.93), whereas above 7.9 g/day the additional benefit diminished (HR = 0.99). Women in the highest fiber tertile had lower risk than those in the lowest tertile for all-cause mortality (HR = 0.85) and CVD mortality (HR = 0.69). Confidence intervals and exact p-values were not provided in the abstract.
Why it matters
This study provides long-term cohort evidence that higher fiber consumption is linked to lower cardiovascular and overall mortality in postmenopausal women, suggesting the largest relative benefit occurs when increasing intake among those with very low baseline consumption.
Limits
Dietary intake was based on 24-hour recalls, which are prone to measurement error, recall bias, and do not capture long-term changes over the 10-year follow-up. As an observational analysis, residual confounding cannot be ruled out. The abstract omitted confidence intervals, fiber tertile cutoffs, and specific cause-of-death breakdown details. Findings are restricted to postmenopausal women.
Cited by
- context The average American woman consumes only about 12 grams of dietary fiber per day.